A Review of Relative Diffusion Analysis and Results

Abstract

Some confusion in the nature and difference between absolute and relative diffusion is found in the work of Kao and Al-Gain (1968) and Kirwan et al. (1978). It is shown that the relative diffusion analysis used by these authors is based on an assumption of independent particle motions. Further, that as this independence implies that relative diffusion statistics asymptote to those of absolute diffusion, Kao and Al-Gain (1968) and Kirwan et al. (1978) have only examined a trivial case of the relative diffusion problem. Although Kirwan et al. (1978) neglect to validate their implicit assumption of independent particle motions, the comparison of their estimates of relative diffusion statistics with absolute diffusion theory is justified. The large-particle separation in their data indicates a near-asymptotic state. Confidence intervals are constructed for their results, which are then shown to be only marginally significant.